Did you see The Aviator? Then you know the story of the Spruce Goose, the flying boat built by billionaire Howard Hughes. It remains one of the largest aircraft ever built, and it made its first flight on this date in 1947. It was supposed to transport personnel during World War II, but it took so long to develop that the war was over by the time the first flight took place. The plane never went into production, mainly because nobody wanted to take a chance on it. But you can see the prototype in a museum in Oregon. [History]